Torque-reducing sleeve for a hydrant stem

Patent metadata

Field	Value
Publication number	US-10458481-B2
Application number	US-201715799131-A
Country	US
Kind code	B2
Filing date	Oct 31, 2017
Priority date	Oct 31, 2017
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A stem coupling for a hydrant includes: an upper portion defining an upper portion length from a center of a plurality of break-away features defined in the stem coupling to a first end of the stem coupling; and a lower portion defining an lower portion length from the center of the plurality of break-away features defined in the stem coupling to a second end of the stem coupling distal from the first end of the stem coupling, the lower portion length equaling at least two times the upper portion length.

First claim

That which is claimed is:

1. A hydrant system comprising:
a hydrant body defining an internal cavity and a central axis, the hydrant body comprising a first constraining portion and a second constraining portion, the hydrant installed and configured to be installed at a bury depth of at least 8 feet 6 inches;
an upper stem positioned at least partly within the internal cavity, an axis of the upper stem substantially fixed about the central axis at the first constraining portion;
a lower stem positioned at least partly within the internal cavity, an axis of the lower stem substantially fixed about the central axis at the second constraining portion; and
a stem coupling securing the upper stem to the lower stem, the stem coupling comprising a coupling body defining a main bore extending from a first end of the stem coupling to a second end of the stem coupling, the main bore sized to receive the upper stem and the lower stem, the coupling body defining a plurality of break-away features, the coupling body comprising an upper portion and a lower portion, the upper portion defining an upper portion length from a center of the plurality of break-away features to the first end of the stem coupling and the lower portion defining a lower portion length from the center of the plurality of break-away features to the second end of the stem coupling, the coupling body defining an internal shoulder proximate to an intersection of the upper portion and the lower portion, the internal shoulder defining a shoulder bore defining a shoulder bore diameter, the shoulder bore diameter being less than an outer diameter of an end of the lower stem that is proximate to the stem coupling, the hydrant defining an upper free length from the center of the plurality of break-away features of the stem coupling to the first constraining portion and defining a lower free length from the center of the plurality of break-away features to the second constraining portion, the upper portion length equal to at least 12 percent of the upper free length of the hydrant but no greater than the upper free length of the hydrant and the lower portion length equal to at least 10 percent of the lower free length of the hydrant but no greater than the lower free length of the hydrant, both the upper stem and the lower stem unsupported between the first constraining portion and the second constraining portion.

2. The system of claim 1 , wherein the stem coupling defines an overall length equal to at least 14 inches.

3. The system of claim 2 , wherein the overall length is equal to at least 20 inches.

4. The system of claim 1 , wherein the main bore is circular in radial cross-section.

5. The system of claim 1 , wherein the first constraining portion is defined by a bonnet of the hydrant.

6. The system of claim 1 , wherein the second constraining portion is defined by a valve assembly of the hydrant.

7. The system of claim 1 , wherein the hydrant is a dry barrel hydrant.

8. The system of claim 1 , wherein a working pressure of the hydrant is at least 350 psi.

9. A stem coupling for a hydrant, the stem coupling comprising:
an upper portion defining an upper portion length from a center of a plurality of break-away features defined in the stem coupling to a first end of the stem coupling and a first distance between the first end of the stem coupling and a first transverse axis defined by a center of a first clearance hole configured to receive a first fastener for securing the upper portion of the stem coupling to an upper stem of the hydrant;
a lower portion defining a lower portion length from the center of the plurality of break-away features defined in the stem coupling to a second end of the stem coupling distal from the first end of the stem coupling and a second distance between the second end of the stem coupling and a second transverse axis defined by a center of a second clearance hole configured to receive a second fastener for securing the lower portion of the stem coupling to a lower stem of the hydrant, the lower portion length equaling at least three times the upper portion length but no greater than a lower free length of the hydrant, the second distance also greater than the first distance; and
an internal shoulder proximate to an intersection of the upper portion and the lower portion, the internal shoulder defining a shoulder bore defining a shoulder bore diameter, the shoulder bore diameter being less than a main bore diameter of the stem coupling.

10. The stem coupling of claim 9 , wherein the lower portion length equals at least two and a half times the upper portion length.

11. The stem coupling of claim 9 , wherein the lower portion length equals at least three times the upper portion length.

12. The stem coupling of claim 9 , wherein the lower portion length equals 3.25 times the upper portion length.

13. The stem coupling of claim 9 , further comprising a first fastener configured to connect an upper stem of a stem assembly of the hydrant to the stem coupling and a second fastener configured to connect a lower stem of the stem assembly of the hydrant to the stem coupling.

14. The stem coupling of claim 13 , wherein each of the first fastener and the second fastener comprises a pin.

15. A stem coupling for a hydrant, the stem coupling comprising:
an upper portion defining an upper portion length from a center of a plurality of break-away features defined in the stem coupling to a first end of the stem coupling;
a lower portion defining a lower portion length from the center of the plurality of break-away features defined in the stem coupling to a second end of the stem coupling distal from the first end of the stem coupling, the lower portion length equaling at least 10 inches but no greater than the lower free length of the hydrant; and
an internal shoulder proximate to an intersection of the upper portion and the lower portion, the internal shoulder defining a shoulder bore defining a shoulder bore diameter, the shoulder bore diameter being less than a main bore diameter of the stem coupling.

16. The stem coupling of claim 15 , wherein the lower portion length equals at least 10 inches.

17. The stem coupling of claim 15 , wherein the lower portion length equals at least 15 inches.

18. The stem coupling of claim 15 , wherein a thickness of the stem coupling is between 4 millimeters and 5 millimeters.

19. The stem coupling of claim 15 , further comprising a coupling body comprising the upper portion and the lower portion, the coupling body defining an internal shoulder extending radially inward from a main bore extending from the first end to the second end of the stem coupling, the internal shoulder defining a shoulder bore.

20. The stem coupling of claim 19 , wherein the shoulder bore has an internal diameter that is less than an outer diameter of an end of an upper stem of a stem assembly of the hydrant that is proximate to the stem coupling and an outer diameter of a lower stem of a stem assembly of the hydrant that is proximate to the stem coupling.

21. A hydrant system comprising:
a hydrant body defining an internal cavity and a central axis, the hydrant body comprising a first constraining portion and a second constraining portion;
an upper stem positioned at least partly within the internal cavity, an axis of the upper stem substantially fixed about the central axis at the first constraining portion;
a lower stem positioned at least partly within the internal cavity, an axis of the lower stem substantially fixed abo

Assignees

• Mueller Int Llc

Inventors

• Li Yanlong
• Gifford Paul
• Wojick Walter Pierce

Classifications

• F16D9/08 Primary

  over a single area encircling the axis of rotation, e.g. shear necks on shafts (F16D9/10 takes precedence) · CPC title

• E03B9/04

  Column hydrants · CPC title

• F16D1/02

  for connecting two abutting shafts or the like · CPC title

• F16K31/508 Primary

  the actuating element being rotatable, non-rising, and driving a non-rotatable axially-sliding element · CPC title

• F16D1/0894

  with other than axial keys, e.g. diametral pins, cotter pins and no other radial clamping · CPC title